Human hair becomes soiled due to its contact with the surrounding atmosphere and, to a greater extent, from sebum secreted by the head. The build-up of the sebum causes the hair to have a dirty feel and an unattractive appearance. The soiling of the hair necessitates it being shampooed with frequent regularity.
Shampooing the hair cleans by removing excess soil and sebum. However, the shampooing process has disadvantages in that the hair is left in a wet, tangled and generally unmanageable state. Shampooing can also result in the hair becoming dry or "frizzy", and a loss of luster, due to removal of natural oils or other hair moisturizing materials. After shampooing, the hair can also suffer from a loss of "softness" perceived by the user upon drying. The hair can also suffer from increased levels of static upon drying after shampooing. This can interfere with combing and can result in fly-away hair. A variety of approaches have been developed to alleviate the after-shampoo problems. These range from the inclusion of hair conditioning aids in shampoos to post-shampoo application of hair conditioners, i.e., hair rinses. Hair rinses are generally liquid in nature and must be applied in a separate step following the shampooing, left on the hair for a length of time, and rinsed with fresh water. This, of course, is time consuming and is not as convenient as shampoos containing both cleaning and hair conditioning ingredients.
While a wide variety of shampoos have been disclosed which contain conditioning aids, they have not been totally satisfactory for a variety of reasons; Cationic conditioning agents are highly desirable for use in hair conditioning due to their abilities to control static, improve wet detangling, and provide a silky wet hair feel to the user. One problem which has been encountered in shampoos relates to compatibility problems between good cleaning anionic surfactants and the many conventional cationic agents which historically have been used as conditioning agents. Efforts have been made to minimize adverse interaction through the use of alternate surfactants and improved cationic conditioning agents. Cationic surfactants which provide good overall conditioning in hair rinse products, in general, tend to complex with anionic cleaning surfactants and provide poor conditioning in a shampoo context. In particular, the use of soluble cationic surfactants that form soluble ionic complexes do not deposit well on the hair. Soluble cationic surfactants that form insoluble ionic complexes deposit on the hair but do not provide good hair conditioning benefits, and tend to cause the hair to have a dirty, coated feel. The use of insoluble cationic surfactants, e.g., tricetyl methyl ammonium chloride, can provide excellent anti-static benefits but do not otherwise provide good overall conditioning. Many cationic polymers tend to build up on the hair to result in an undesirable, "unclean" coated feel. Cationic polymers therefore, conventionally, are preferably used at limited levels to minimize this problem. This, however, can limit the overall conditioning benefits that are obtained. Additionally, cationic conditioning agents commonly do not provide optimal overall conditioning benefits, particularly in the area of "softness ", especially when delivered as an ingredient in a shampoo composition.
Materials which can provide increased softness are nonionic silicones. Silicones in shampoo compositions have been disclosed in a number of different publications. Such publications include U.S. Pat. No. 2,826,551, Geen, issued Mar. 11, 1958; U.S. Pat. No. 3,964,500, Drakoff, issued Jun. 22, 1976; U.S. Pat. No. 4,364,837, Pader, issued Dec. 21, 1982; and British Patent 849,433, Woolston, issued Sep. 28, 1960. While these patents disclose silicone containing compositions, they also did not provide a totally satisfactory product in that it was difficult to maintain the silicone well dispersed and suspended in the product. Recently, stable, insoluble silicone-containing hair conditioning shampoo compositions have been described in U.S. Pat. No. 4,741,855, Grote and Russell, issued May 3, 1988 and U.S. Pat. No. 4,788,066, Bolich and Williams, issued Nov. 29, 1988. These shampoo compositions can deliver excellent overall conditioning benefits to the hair while maintaining excellent cleaning performance, even with the use of anionic detersive surfactants, for a wide variety of hair types.
More recently, improved conditioning shampoos were provided in U.S. Ser. No. 07/622,699, Robert L. Wells, filed Dec. 5, 1990, now abandoned, and its continuation application Ser. No. 07/778,765, filed Oct. 21, 1991, now abandoned wherein shampoos containing anionic surfactant, dispersed, insoluble silicone, and certain relatively low ionic strength cationic polymers (greater than about 0.4 meq./gm) were disclosed. These compositions provide excellent hair cleaning conditioning to a wide variety of hair types, especially including improved conditioning to hair damaged by color treatments, bleaching, permanents, etc.
Japanese Patent Application, Laid Open No. 56-72095, Jun. 16, 1981, Hirota et al. (Kao Soap Corp.) also discloses shampoo containing cationic polymer and silicone conditioning agents. Still other patent publications relating to shampoos with cationic agents and silicone include EPO Application Publication 0 413 417, published Feb. 20, 1991, Hartnett et al.
Another approach to providing hair conditioning benefits to shampoo compositions has been to use materials which are oily to the touch. These materials provide improved luster and shine to the hair. Oily materials have also been combined with cationic materials in the shampoo formulations. Japanese Patent Application Showa 53-35902, laid open Oct. 6, 1979 (Showa 54-129135), N. Uchino (Lion Yushi Co.), discloses hair treatment compositions containing cationic polymer, fatty acid salt, and at least 10% of an oily component for use before or after shampooing. Suitable oily components are hydrocarbons, higher alcohols, fatty acid esters, glycerides, and fatty acids. Japanese Patent Application 62 [1987]-327266, filed Dec, 25, 1987, published Jul. 4, 1989, laid open No. HEI 1 [1987]-168612, Horie et al., discloses detergent compositions containing cationic surfactant and/or cationic polymer, anionic surfactant, and specific esters of the formula RCOOR' wherein R and R' are straight or branched chain alkyls.
In spite of these attempts to provide optimal combinations of cleaning ability and hair conditioning, it remains desirable to provide further improved hair conditioning shampoo compositions. For instance, it remains desirable to improve overall conditioning, and especially shine and luster, wet and dry combing, and dry hair feel, of hair treated with shampoo containing silicone and cationic material. For shampoos containing oily materials in combination with cationic materials, it remains desirable to improve overall conditioning, especially wet combing and detangling, dry combing, and dry hair feel. However merely increasing the level of one or both conditioning ingredients can result in adverse effects such as greasy hair feel and loss of fullness. It is desirable to improve conditioning without suffering from these drawbacks.
One attempt to do this is disclosed in EPO Patent Publication No. 0 413 416, published Feb. 20, 1991, Robbins et al., which discloses shampoo containing aminosilicone, anionic surfactant, cationic surfactant, and a hydrocarbon component. These types of formulations would normally be expected to result in either excessive buildup of aminosilicone on the hair, and consequently greasy hair feel and loss of fullness, or a relatively limited degree of improvement due to intentional use of very low levels of aminosilicone to avoid such adverse effects. The cationic surfactants would have limited ability to condition the hair due to interaction with the anionic surfactant.
EPO Patent Application Publication No. 0 413 417, published Feb. 20, 1991, discloses shampoo containing anionic surfactant, and conditioning agents such as insoluble silicone (preferably aminosilicone), cationic surfactant, polyethylenes, paraffins, microcrystalline waxes, C.sub.18 -C.sub.36 fatty acids or triglycerides, high fatty alcohol esters of high fatty acids, and beeswax. Another patent document which discloses shampoo compositions and a variety of conditioning agents is U.S. Pat. No. 3,964,500, Drakoff, issued Jun. 22, 1976. This patent relates to shampoo containing silicone conditioner and a hair bodying agent selected from certain wood rosins, shellac, sucrose acetate isobutyrate, and cationic amino cellulose.
A recent approach to providing hair conditioning benefits to shampoo is described in U.S. Pat. No. 5,085,857 (Reid et al.). The composition disclosed combines a surfactant system (selected from anionic, nonionic, or amphoteric, or mixtures thereof), cationic guar derived polymer, and nonvolatile silicone having particle size less than 2 microns. Without being limited by theory, Applicants have found that by utilizing a select cationic cellulose derived polymer in place of the cationic guar derived polymer in a specific surfactant system, which optimizes the conditioning coacervate formed, the present invention results in significantly improved conditioning performance.
In spite of all these approaches and attempts to provide optimum combinations of shampoos and hair conditioners, it remains desirable to provide still improved conditioning shampoos. It has now been found that improved overall conditioning can be achieved by combining a specific surfactant component comprising an ethoxylated alkyl sulfate surfactant having from about 1 to about 8 moles of ethoxylation and an amphoteric surfactant in a shampoo with insoluble, dispersed, nonionic conditioning agent, select synthetic esters and a soluble cellulosic cationic organic polymer hair conditioning agent. These compositions can provide improved conditioning while reducing the level of undesirable side effects that can result from increasing the level of conditioning agent in prior known conditioning systems. As discussed previously, a conditioning agent system containing too much silicone can result in silicone build up on the hair over repeated usages and to loss of fullness of the hair. Too much oil results in an oily feel and a loss of fullness of the hair. Too much cationic conditioning agent results in a coated, dirty feel of the hair. Now it has been found that the components of the present invention can provide improved overall conditioning while minimizing the adverse effects of conditioning agent build-up that otherwise can be incurred upon increasing the levels of individual components in prior known conditioning systems. It has now been found that by adding select synthetic esters improves conditioning benefits.
It is an object of this invention to provide shampoo compositions, which can provide excellent cleaning performance and improved levels of conditioning while minimizing any adverse side effects associated with build-up due to the use of excess conditioning agent.
It is also an object of this invention to provide a method for cleaning and conditioning the hair which can provide excellent cleaning in combination with improved conditioning, while minimizing adverse side effects associated with excess build-up of conditioning agent on the hair.
These objects will become apparent from the description which follows, as may other objects become apparent upon a reading of said description.